// The functions below were copied and modified from golang.org/x/crypto/sha3.
//
// Copyright (c) 2009 The Go Authors. All rights reserved.

// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:

//    * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//    * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
//    * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.

// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

//go:build (!amd64 && !386 && !ppc64le) || purego
// +build !amd64,!386,!ppc64le purego

package hash

import (
	"encoding/binary"
)

// copyOut copies 32 bytes to a hash array.
func copyOut(d *state) Hash {
	var out Hash
	for i := 0; i < 4; i++ {
		binary.LittleEndian.PutUint64(out[i<<3:], d.a[i])
	}
	return out
}

// copyIn512 copies two 32 bytes arrays into the state and writes the padding;
// it makes no non-portable assumptions about memory layout
// or alignment.
func copyIn512(d *state, buf1, buf2 Hash) {
	sliceBuf1, sliceBuf2 := buf1[:], buf2[:]

	var i int
	for ; i < 4; i++ {
		d.a[i] = binary.LittleEndian.Uint64(sliceBuf1)
		sliceBuf1 = sliceBuf1[8:]
	}
	for ; i < 8; i++ {
		d.a[i] = binary.LittleEndian.Uint64(sliceBuf2)
		sliceBuf2 = sliceBuf2[8:]
	}
	// copy the dsbyte
	// dsbyte also contains the first one bit for the padding.
	d.a[8] = 0x6
	// copy the last padding bit
	d.a[16] = paddingEnd
}

// copyIn256 copies a 32 bytes array into the state without padding.
// it makes no non-portable assumptions about memory layout
// or alignment.
func copyIn256(d *state, buf Hash) {
	sliceBuf := buf[:]

	for i := 0; i < 4; i++ {
		d.a[i] = binary.LittleEndian.Uint64(sliceBuf)
		sliceBuf = sliceBuf[8:]
	}
}
